- ligmanets and tendons attach to the bone, the collagen fibers of these structures go into the bone tissue to anchor these structures

Endosteum:

what is this?

where are these located?

what does it consist of?

- cellular layer that lines the cavaties on the interior of bones.

- marrow cavity of shafts of long bones- cavities within spongy bone

- osteoprogenitor cells

Bone marrow:

what type of tissue? which is?

amount of liquid and reticular fibers? ECM?

vascular or a vascular?

- Hemopoietic tissue: special CT that forms blood cells

- modest amount of liquid and has a fine network of reticular fibers

- highly vascular

Bone marrow:

two types? major differnce?

Red Bone Marrow:- actively hematopoietic form of bone marrow

Yellow Bone Marrow: inactive form of bone marrow, but cna be converted into red bone marow

Blood Supply:

how does blood get inside?

what is this called?

how does blood move within the bone?

how is the bone tissues supplied?

- there are openings in the outer surface of bones for blood vessels (and nerves) to gain entry into the bone

- nutrient formaina

- works from the inside to the outer edges (centrifugal)

- volkmann and haversian canals

Compact Bone:

what are haversian systems (osteons)

what in the center of each haversian system?

what surronds the haversian canal?

what in between the concnetric lamellae?

what connects between neighboring lacunae

whats forms within the canaliculi

- cylindrical units run parallel to the long axis of the bone- Haversian canal: a space that contains the avascular and neural supply- concentric lamellae of bone matrix: type 1 collagen fibers that run parralel to eachother- Lucanae: which contains osteocytes- Canaliculi: small tunnels in the bone matrix that connect them in a radial pattern and contian osteoctes and there are no blood vessels- Gap junctions: adjacent osteocytes meet-

Compact bone:

the osteocytes nearest the blood supply do what?

pick up nutrients from the blood and share with neighboring osteocyte

Interstitial lamellae:

what is this?

what do they represent?

- these are lamellae that do not belong to any haversian system

- represent old concnetric lamellae

Outer circumfrential lamellae:

what are these?

- these are concentric lamelae that are internal to the periosteum

- - they do not belong to any haversian system

inner circumferential lamellae:

what are these?

- concentric lamellae that are immediatley external to the endosteum

- they do not belong to any haversian system

Volkmann canals:

what are these?

what do they connect?

- channels for blood vessels and nerves that run perpindicular to the haversian canals

- the haversian canals of different haversian systems

Compact bone (decalcified) (low magnification)

what happens with the bone matrix

what stains pink (eosinophilic)

what stains purple (basophilic)

- the hydroxyapatite crystals are dissolved and removed, but the bone cells and the organic parts of the bone matrix are preserved

- eosinophilic staining quality because of all of the collagen present

- with the basophilic nature of the matrix of hyaline cartilage.

Compact bone (ground) (medium magnification):

what is the histological viewing known as?

- ground bone: effectively removes all of the organic parts of the bone and leaves the inorganic portions of the bone matrix

- purple since they have so much RER and well developed Golgi aparatus

Osteoblasts:

what if they are actively producing bone matrix?

what is they are relatively

are they mitotic?

polar or non-polar?

- they are usally cuboid or polyhedral in shape

- they usally appear somewhat flattened

- osteblasts are mitotic

- they are mostly polar in nature

Osteoblasts:

what do they usually only secrete on one side of the cell?

what happens when osteoids secretes from all other sides?

what happens when the lacuna is fully formed

- secrete osteoid

- this creates a lacuna

- the cell inside is NO longer known as a osteoblast it is known as a osteocyte

Osteocyte:

where is this found?

what do they do?

are these mitotic?

where are there processes found?

what does this arrangemtn allow?

- lucunae

- maintain the bone tissue by a continual process of turning over the molecules of the bone matrix

- they are not mitotic

- canaliculi

- communication and diffusion between neighboring osteocytes by way of gap junctions

Osteocyte:

what is a dimineralized preparation?

what is the bone matrix? (eosinophilic or basophilic)

how is a ground bone preparation made?

whats the point of this preparation of this preperation

- bone tissue is chemically treated to take out the calcium salts in order to make it soft enough to section

- eosinophilic because the collagen is present

- grinding the bone tissue thin enough that light to be transmitted through

- preserves the structure of the bone matrix

Osteoclast:

what are these responsible for?

what is the shallow depression these are found in?

size and nucleation?

what cell lineage are they derived from?

- bone resorbtion

- resorption bay or howship lacuna

- large and multinucleated (since cells will coalesce to form one osteoclast)

- same cell lineage as monocytes

Immature bone:

Main differnces between histiological appearance of mature and immature bone?

(1) actively growing bony surfaces are lined with a row of osteoblasts and the cells that form the unmineralized bone matrix known as osteoid(2.) usually a thin layers of osteoid can be seen on the actively growing surface of the bone (adjacent to the osteoblasts)(3.) immature bone is non-lamellar, no recognizeable architecture in the bony tissue

Immature bone:

two type of bone formation?

- Intramembraneous

- Endochondral

Intramembranous formation:

how does the bone develop?

how do they differentiate?

what type of bones are formed by this?

- directly from the mesechyme (membrane)

- directly into the osteoblasts (make the bone tissue)

- flat bones

Endochondral bone formation:

where will the mesenchyme first form?

mesenchyme cells differntiate into?

what is catilage then converted into? occurs where?

what do the sendodary ossification centers add too?

- hyaline cartilage

- chondroblasts

- bone tissue by osteoblasts and occurs at the primary ossification centers and secondary ossification centers

- add features the ends of bones (tubercules) and allow the bone to increase in length during childhood

- osteocytes- osteoid- mesenchyme- osteoblasts- marrow cavity

Intramembranous bone development (decalcified) (high magnification):

what helps determine ehat type of develpment?

what happens in a developing bone?

what does the marrow cavity contain?

- osteoblasts lining one of the surfaces of the bone tissue

- single row of cuboidal/polyhedral cells (the osteoblasts) is always present on the side of the bone tissue that is actively growing

- External: the process in which the shape of the entire bone can be changed

Internal remodeling:

steps?

(1.)bone matrix is reabsorbed by osteoclasts resulting a space called resorption canal(2.)capillaries invade the resorption canal(3.)osteoblasts form new bony lamellae, starting peripherally and working toward the center forming a haversian canal (newer is nearer the center)

External remodeling:

what are the two opposite processes?

- Osteoblasts form on the outer edge of the done tissue

- AND add new bone tissue to outer surface of the entire bone

important things to know about the remodeling of internal and external?

osteocytes need to be replaced continually

a bone under more stress more bone mass will be added to it

wolf law: bone develops the structure most suited to resist the forces acting upon it

bone is a reservoir of calcium that the body uses to maintain blood calcium levels

Osteoporosis:

what is this?

- a disease that causes an abnormal reduction in bone mass that can lead to fractures

Fibrous Joint (synarthrosis):

what is this?

amoutn of movement?

- the union of bony elements by continuous intervening fibrous tissue

- very limited movement

Cartilagenous joint:

what is this?

type of cartillage?

if it is Intervening fibrocartilage the joint is known as?

if the intervening hyaline cartiallge what is the joint known as?

amount of the movement?

- the union of bony elements by intervening cartillage

- fibrocartillage

- symphysis

- synchondrosis

- moderate amount of movement

Synovial joint (diarthrosis):

4 major characterisitics?

- Joint capsule (fibrous capsule): composed of dense regular collagenous CT that surroudns the joint - Joint space: joint capsule defines this space filled with synovia- synovial membrane: secretes the synovia and it lines the inside of the joint and is composed of squamous/cubidal cells and NO basement membrane- articular cartillage: portions of the bones inside the joint capsule are lined with this, which is hyaline cartialge, with NO perichondrium, provides smooth surface for ease of movemnt